An organic light emitting diode (OLED) has some characteristics that cannot be realized by traditional light sources, such as high quantum efficiency, large area lighting, power saving, lightness, thinness and flexibility and so on. However, the light-emitting layer of an OLED device is easily degraded by penetration of moisture and oxygen, thus shortening the lifetime of the OLED device. Hence, the packaging of an OLED device is very important.
In view of current applications of OLED technology to lighting tools, since a proper barrier against moisture is needed for the light-emitting layer or the cathode layer, for assembling the OLED device to lamps or other lighting devices, it is usually necessary to pair the OLED device with additional refined equipments.